•13th Internat. Conference on Extending Data Base Technology, EDBT’08 Nantes,  Tutorials and Panels Chair.

•12th Internat. Conf. On Applications of Natural Language To Databases NLDB’07 Paris, General co-Chair.

•1st Internat. Conf. on Semantics of a Networked World: Semantics for Grid Databases (IFIP-ACM) IC-SNW Paris, General Chair.

•20th Internat. Conf. on Conceptual Modeling ER’01 Yakohama, Japan, European Coordinator.

•5th Internat. Conf. On Applications of Natural Language To Databases NLDB’00 Versailles, General Chair.

•4th Internat. Workshop on Knowledge Bases meet Databases KRDB'00, Berlin, Germany, Organization co-Chair.

•18th Internat. Conf. on Conceptual Modeling ER’99  Paris, Prog. Committee co-Chair.

•7th Internat. Conference on Extending Data Base Technoly EDBT’96  Avignon, Organization  Chair.

•1st Internat. Workshop On Applications of Natural Language To Databases, NLDB'95 Versailles, Prog. Committee Chair.

•International Workshop on Data and Services Management in Mobile Environments , DS2M’08

•ACM Conf. on Information and Knowledge Management CIKM‘2007

•Internat. Conf. on Very Large Databases, VLDB’1994, 2001, 2002

•Internat. Conf. on Extending Database Technology, EDBT‘2006

•Internat. Conf. On Advanced Information Systems Engineering, CAiSE’1992, 2004, 2005, 2006, 2007, 2009

•Internat Conf. on Conceptual Modeling

•ER/CM’1986, 1992, 2000, 2002, 2003, 2004, 2007, 2008, 2009

•Internat. Conf. on Cooperative Information System, CoopIS’1999, 2000, 2005

•Internat. Conf. on Semantics of a Connected World: Semantics fir Grid Databases (IFIP-ACM), IC-SNW’ 2006

•Internat. Conference On Applications of Natural Language To Databases and Information Systems, NLDB’1996, 1997, 1998, 1999, 2001, 2002, 2003, 2004, 2005, 2006,2008,2009

•Internat. Workshop on Rules in Database Systems, RIDS’1993, 1995, 1997

•Internat. Conf. on Information Integration and Web-based Applications Services, IIWAS’2005, 2006

•Internat. Conf. on Business Process Management, BPM‘2005

•International Workshop on Data warehousing and OLAP, DOLAP’2000, 2001, 2002, 2003, 2004, 2005

•Internat. Workshop on Data Integration over the Web, DIWEB‘2004

•Internat. Workshop on Design and Management of Data Warehouses, DMDW1999, 2000, 2003

•Internat. Conf. on Data Warehousing and Knowledge Discovery, DaWaK’2005, 2006, 2007

•Internat. Workshop on Quality of Information Systems, QoIS’2005, 2006

•Decision Systems Engineering Workshop, DSE‘2003

•Eurasian Conf. on Advances in Information & Communication  Technology, Eurasia‘2002

•Internat. Worshop on Database Maintenance and Engineering, DBMR‘2002

•Internat. Workshop on Knowledge Bases meets Databases, KRDB’1999, 2000